Dance Anatomy & Kinesiology

486 Dance Anatomy and Kinesiology

improving hamstring flexibility with supplemental

stretching exercises could improve performance if

hamstring tightness is a limiting factor. One way to

quickly ascertain if strength or flexibility is a limiting

factor is to compare passive range of motion to the

range used by the dancer during execution of the

movement (Tests and Measurements 8.1). If passive

range of motion is close to that achieved actively,

this suggests that improving flexibility would likely

help improve the range utilized in the movement.

However, if the range achieved passively is mark-

edly higher than achieved in the movement, this

suggests that flexibility is not limiting and that

strength or activation patterns, or both, are more

likely implicated.

Analysis of potential muscle constraints can also

be useful for predicting and lowering injury risk.

Multijoint muscles such as the hamstrings that are

required to undergo extreme elongation appear

to be at greater risk for being strained. Although

this is a complex and controversial area, perform-

ing supplemental exercises for these muscles to

develop adequate flexibility, adequate strength,

balanced strength between right and left sides for

the same muscle, and balanced strength between

the muscle of concern and its antagonist will likely

reduce injury risk.

Lastly, evaluation of alignment and technique

factors can reveal factors that, when corrected,

can enhance performance, help develop general

dance skills, and in some cases reduce injury risk.

For example, analysis might reveal that a dancer is

excessively arching his or her back during the front

kick. This movement pattern, considered undesired

Comparison of Passive and Active Range of Motion

for a Grand Battement

Perform the screening test for hamstring flex-

ibility described in chapter 4 (Tests and Mea-

surements 4.4, p. 205) on yourself by using

one hand to lightly bring one leg toward your

shoulder while the back of the other leg stays

in contact with the floor, as shown in the figure

(A). Compare the angle of hip flexion derived

passively with this hamstring test to the range

of hip flexion exhibited when actively raising

the leg to the front at a relatively slow speed

(B). An easy way to practically compare these

measurements is to note the height of your foot

relative to your head and trunk. If the passive

hamstring test results (hip angle) are low rela-

tive to desired values for dancers and the foot

height is close to the level achieved actively, the

hamstrings are likely serving as constraints, and

hamstring stretching would be recommended to

help improve battement height. However, many

dancers achieve a much greater range passively

than they can achieve actively, especially in

movements such as slow front extensions in

which momentum cannot be of much help. In

such cases, the hamstrings are likely not the

primary limiting constraint, and focus should

move to strengthening the hip flexors (iliopsoas

emphasis) and optimizing technique.

TESTS AND MEASUREMENTS 8.1

A

B